HFRR standard specimens are sold as a pack of 100 upper and 100 lower specimens. The upper specimen is a 6mm diameter ball that is loaded into the upper specimen holder, and the lower specimen is a 10mm disc that is loaded into the lower specimen holder.
The specimens are manufactured to comply with ISO 12156-1, ASTM D6079, ASTM D7688 and IP450 diesel fuel standard test methods.
Upper Specimen (Ball)
The upper specimen is specified to grade 28 (ANSI B3.12), ANSI E-52100 steel, with a Rockwell hardness “C” scale (HRC) number of 58-66 (ISO 6508), and a surface finish of less than 0.05 µm Ra.
Lower Specimen (Disc)
The lower specimen is specified to AISI E-52100 steel machined from annealed rod, with Vickers hardness “30Hv” scale number of 190-210 (ISO 6507/1). It is turned, lapped and polished to a surface finish of less than 0.02µm Ra.